Abstract: Due to the difference in the system scale, software architecture mode and system integration technology, the problems of difficult data integration and function sharing etc. exist in the current water conservancy information system, resulting in the formation of "information island". Service-Oriented Architecture (SOA) has the advantages of low coupling, cross-platform, easy maintenance and well scalability, etc., which can realize data integration and function sharing, and effectively solve the "information island" problem via sound interface and service. Based on Flex platform and SOA architecture, a flood control management information system is developed, which achieves the functions of GIS service, hydrological monitoring data management, flood control scheduling scheme comparison and selection, and flood evolution simulation. A detail introduction to the design and realization of flood control management information system is given from three aspects such as system architecture, key technologies, and UI to provide a reference for the construction of water conservancy information system in the future.